Hello,
I have a building of 8 appartments with 100A Panelboard for each appartment. Each panel is fed by 50 mm2 cable from a main distribution board which is around 50 meter away from the building. So 8 cables are coming into the building.
What is the enough size for a grounding ring cable that will go around the building? Following 250.66 will 25 mm2 of cable ring around the building be enough?
Is following 250.52(A)(4) minimum conductor size of 2 AWF is a must in this case?
Same question for another building with 59 appartments + 59 panels + 59 Feeders of 50 mm2 for each appartment? what would be the minimum size here?
Many thanks
I have a building of 8 appartments with 100A Panelboard for each appartment. Each panel is fed by 50 mm2 cable from a main distribution board which is around 50 meter away from the building. So 8 cables are coming into the building.
What is the enough size for a grounding ring cable that will go around the building? Following 250.66 will 25 mm2 of cable ring around the building be enough?
Is following 250.52(A)(4) minimum conductor size of 2 AWF is a must in this case?
Same question for another building with 59 appartments + 59 panels + 59 Feeders of 50 mm2 for each appartment? what would be the minimum size here?
Many thanks